The hypothesis is: the most permeating constituent of the challenge medium containing a pesticidal emulsion concentrate regulates the permeation of the pesticide through glove and garment materials. The initial studies will involve identification and quantification of the inert components and surfactants/adjuvants in the selected emulsion concentrates. The latter contain the following pesticides: captan, chlorpyrifos, 2,4-D (three forms), endosulfan, malathion, methomyl, methyl parathion, and trifluralin. The selected glove materials are: Butyl, Nitrile, Silver Shield, and Viton. The garment materials are: Barricade, two-ply Saranax-Laminated Tyvek 23-P, Chemrel Max and Teflon/Nomex/Teflon. Eight-hour screening studies with two ASTM-type permeation techniques will then be performed. One technique involves a I-PTC ASTM-type permeation cell and liquid collection system. The other method utilizes a solid silicone sheet collection method. Challenges to the materials will be to the emulsion concentrates, and to the aqueous emulsion diluted to its highest spraying concentration. Other challenges will include the pesticide dissolved in the major constituent of the inert components in the presence and absence of adjuvant/surfactant. Shelf-life studies for materials aged 0.5 and 1.0 years after acquisition will also be performed. The screening studies will allow selection of the appropriate permeation method and of gloves/garments for the kinetics phase of the research. The latter will result in characterization of the permeation of the materials at three different temperatures and different challenge/collection conditions. A mathematical model will then be developed.